Power quality devices are, typically, designed to be as small as possible. Rack mounted devices, for instance, are typically restricted to one rack unit to occupy as little space in the equipment rack as possible. Cord connected devices are also limited in size as they are often placed or mounted in a restricted space behind the equipment that they are protecting.
SPDs and PDUs are usually designed to protect a system of equipment and, as such, usually contain several AC receptacles. In addition to the AC receptacles, cord connected devices also have an AC power cord, and may include a switch, over-current protection (i.e. panel mounted fuse or circuit breaker) diagnostic indicators and display. In addition to protecting connected equipment from AC mains transients and EMI, many SPDs and PDUs also include circuitry to protect connected equipment from telephone (modem/fax protection) and Ethernet transients. For each of these circuits a pair of connectors (i.e. modular jacks) is required; one for connection of device to wall outlet and the other for connection of device to protected equipment.
These small devices can be placed at the site of the equipment being protected and can protect the device, as well as collect information about the kinds of power events the device has detected. As information about AC mains transients and EMI can be valuable to in-field technicians, power device engineers have developed some power quality devices that include communication systems that allow the devices to interface with and communicate with a remote system. In this way, data about such transients and EMI events can be downloaded from the power quality device and viewed by the technician. Typically, the engineers have included serial communication interfaces that have some type of dedicated connector, typically a modular jack or a D-sub connector, that supports serial communications. Other devices employ optical communication systems that have an optical transducer for communicating data to a remote station. One such system is the Power Doctor II that is a hand held system that a technician can hold in front of the power quality device so that data can be delivered across an optical interface from the power quality device to the Power Doctor II. Data collected into the Power Doctor II can be downloaded through to a standard PC via a USB interface.
Although these power quality devices can work well and can communicate important data, there remains a need in the art for improved systems.